1. Field of the Invention
The present invention related to discharge lamp unit, more particularly, a discharge lamp unit having a supporting member that supports the discharge lamp therein.
2. Description of the Related Art
Conventionally, a discharge lamp unit provided with a supporting member that supports the discharge lamp, circuit components that supply power to the discharge lamp unit (i.e., circuit elements including an inductor, a capacitor and a circuit board including an integrated circuit or IC), and a casing member are known. The casing member is provided with the circuit components being retained inside thereof and the supporting member being exposed outside of the casing member.
As an example of the casing member that constitutes the discharge lamp unit, Japanese patent application laid-open No. 2003-022702 discloses a casing member in which a supporting member side is made of resin having low thermal conductivity and the opposite side of the supporting member is made of metal having high thermal conductivity.
However, in the above-described discharge lamp unit, when the unit includes a self-heating component that radiates heat by itself, the circuit components arranged closely to the self-heating component, are likely to be heated by the heat conducted from the self-heating component which is at high temperature.